Ben Greenwood is continuing his apprenticeship at the Royal Institute of Magic, hoping things will be slightly less complicated now that he has advanced to the second grade. Fat chance. Coupled with the sterner challenges that the second grade brings, there is also the small matter of the impending dark elf invasion, making life at the Institute even busier than usual. Ben is the only one who can stop them, by finding Elizabeth's Armour and its Guardians. Ben has retrieved one piece of the Armour – the boots – but the rest remain hidden. He has just one clue, which could lead to Elizabeth's Helm: an old black and white photo given to him by the Master of Apprentices. Ben must split his time between his apprenticeship and searching for the helm, before the dark elves strike and all hell breaks loose. The Protectors is the third book in the Royal Institute of Magic series.